I’ve not seen that type of dress with a straight hem so it’s hard for me to imagine. However, I do think that the bubble hem suits the dress better than what a straight hem would. It makes the fabric appear draped and it looks very pretty with the diagonal flow.

I think it will look unfinished if you remove the b-hem… because of the style of the dress, I believe it “needs” the bubble hem.. Besides, it doesn´t really look like a bubble at all, it just gives it a softer end. So I would keep the bubble hem.